Torsion bar for moderate exercise of arms and shoulder



May 5, 1970 l. J. FERDINAND TORSION BAR FOR MODERATE EXERCISE OF ARMSAND SHQULDER Filed Aug. 8, 1968 Q Q 0,020 A'A'A F I9. I

FIG.3

lNVf/VTO/P. IRWIN J. FERDINAND 20 y C% ATT'Y 26 Ill. 26

IIMIL United States Patent 3,510,130 TORSION BAR FOR MODERATE EXERCISEOF ARMS AND SHOULDER Irwin J. Ferdinand, Glencoe, IlL, assignor to HirshCompany, Skokie, 11]., a corporation of Illinois Filed Aug. 8, 1968,Ser. No. 751,193 Int. Cl. A63b 21/05 U.S. Cl. 272-67 8 Claims ABSTRACTOF THE DISCLOSURE A tubular torsion bar of rolled metal of an optimumlength and girth with a bipartite wall having a longitudinal slitextending from end to end for optimum torsional resilience. Hand gripsare provided on each end to permit the bar to be gripped and operatedtorsionally as an exercise apparatus for isotonic contraction andrelaxation of muscles of the arms and shoulders by the repeatedapplication and release of manual forces sufficient to substantiallystress the bar torsionally in either one of both directions equally.

BACKGROUND OF THE INVENTION A wide variety of manual exercise deviceshave been provided of physical and neurological values which serve invarying degrees to promote isotonic contraction and relaxation of themuscles of the fingers, wrists, forearms, elbows, upper arms and theshoulders of a persons body. Examples of the prior art would includecoiled heavy spring wire having handles gripped by one hand and squeezedthereby exercising the muscles of the hand, wrist and forearm. The.movement is substantially planar. Resilient stretch devices with handgrips at each end are generally stretched in a direction laterally fromthe body to exercise the pectoralis and deltodeus muscles and also thebiceps brachii and triceps brachialis muscles of the upper extremity.Weight pulling and weight lifting devices generally including cords andpulleys, to exercise the triceps brachialis muscles, and, a variety ofbarbells, etc., raised to various heights and at various angles from thebody only require an effort of constant magnitude 'throughout theirmovement.

All of these have limited application, or require extensive or built-inequipment and most are inconvenient for casual and repeated moments ofuse during the day. None of them have the quick appeal and interest ofbeing taken from a table or drawer and used personally or competitivelyeven in the middle of conferences with other people, dictation, orthoughtful relaxation. The abstraction of muscle movement evenunconsciously, such as the wiggling of a foot while in thought, assistsconcentration and attentiveness essentially because of assisting bloodcirculation by muscle contraction and relaxation.

It is well known that muscle contraction is a series of twiches inducedneurologically by rapidly recurrent impulses transmitted by motor nervesrelated to sensory perception, the duration and strength of whichdetermines the extent and effort of contraction. In the presentinvention, all of the muscles mentioned are exercised in the repeatedapplication of a manual force sufficient to subject the tubular barembodying the invention to a substantial torsional stress in eitherdirection, and alternately in both directions, within the capaciabilityof the bar without permanent deformation thereof. The longitudinal slitherein mentioned which gives the bar this property by permitting theedges defining the slit to move relative to each other in aplanar-helical complex that is parallel to the longitudinal axis of thebar when the bar is subjected to torsional stress, distorts any given Ccross section 3,510,130 Patented May 5, 1970 ice through the bar form aresting planar orientation to a helical three dimensional orientationunder resilient tension. The edges defining the slit slidably engageeach other longitudinally and the C sectional form of the bar maintainsthem against oil-setting and over-lapping each other against weakeningof the bar under applied torsional stresses. The exercise bar providesan uncomplicated structure with minimum components and is completelysafe for use by anyone. It further offers both ease and low cost ofmanufacture, as well as ease in packaging. Similarly, its light weightand its streamlined, compact form and size makes it easy to store andhandle.

SUMMARY OF THE INVENTION This invention relates to a tubular member ofsheet metal strip roll-formed to a modified C cross-sectional shape withwork hardened transversely stiffened corners or ribs of a girthcomfortable to grip and of optimum length and resilience to handle. Handgrips are secured on each end and a straight-line longitudinal slit onone side only, extending from end to end, permit the edges defining theslit to slide relative to each other in a plane parallel to thelongitudinal axis of the member when such member is twisted in eitherdirection, the total relative rotation being within the range of anddepending on the effort exerted by the user in the application of amanual torsional force. The device is adapted for use as an apparatusfor the exercise of the muscles of the upper extremity by promotingtheir isotonic contraction and relaxation.

DESCRIPTION OF THE DRAWINGS FIG. 1 is a perspective view of the torsionbar exercise apparatus in its resting position illustrating thelongitudinal slit from end to end;

FIG. 2 is a smillar view of the torsion bar exercise apparatus in atensioned position;

FIG. 3 is a cross-sectional view of the torsion bar exercise apparatus;

FIG. 4 is a cross-sectional view of an alternative embodiment of thetorsion bar exercise apparatus;

FIG. 5 is a detailed view of a hand grip disposed on end of the torsionbar exercise apparatus;

FIG. 6 is a vertical sectional view taken along the line 66 of FIG. 5;and

FIG. 7 is a plan view of a torsion scale employed with the invention.

DESCRIPTION OF THE PREFERRED EMBODIMENTS In describing the invention, anoptimum length is approximately the overall distance between theshoulders of the user, and an optimum torsional resilience is thecapability of the bar to withstand up to 180 total deflection from endto end without permanent deformation, the essential working rotationalangle being that which the hands gripping the handles are capable ofinducing when the forearms remain parallel.

In FIG. 1 the tubular bar 10 is shown in its resting position as grippedby fingers and hands 12 ready for exercising. The bar may be grippedwith any side up but for convenience of description is shown with theside 14 observable which has the slit 20 defined by the side edges 16extending the full length of the bar. For purposes of illustration andfor competitive scoring, if desired, index marks 22 are shown as placedon opposite sides of the slit 20. In the resting position of the bar themarks are in registration with each other as shown. The single lineindex marks are representative of comparison scales 44 (FIG. 7) suppliedon the article itself either by embossing or by decals 48 in which acenter line 50 locates the 3 decal which then is Severed therealong by aknife edge following the slit.

The longitudinal slit 20 is defined by the side edges 16 permits the barto be twisted about the longitudinal axis by the edges defining the slitsliding longitudinally relative to each other. The edges 16 abut andslide against each other and the extent of the longitudinal displacementof the edges is a measure of the extent the bar is twisted and thetorsional effort exerted by the user.

The preferred cross-sectional form is shown in FIG. 3 which isessentially hexagonal with four major walls 24, including the wall 14having the slit in it, and four minor walls 26 in the nature of recessmitered corners which provide work hardened ribs 28 in the form rollingthereof. The walls and corners cross-sectionally define a rectangular orsquare C-shaped rigidified by the work hardening against relativelateral displacement of the edges 16 in use. By way of example, a stripof .028 thick quarter-hard, cold-rolled steel strip approximately 2.59"wide is rolled to the shape shown in FIG. 3.

With moderate effort an average person can twist the bar to the extentshown in FIG. 2. The bar 10a shown in FIG. 4 has four instead of eightwork hardened ribs 28, but dimensionally both provide a girth that iscomfortable to grip for exercise and an excellent radius of gyrationfactor which prevents a bending of the bar, either under the end thrustsor laterally applied moments of force.

Although the bar can be gripped and twisted as described thus far, andis completely safe to handle in this form because the work hardened ribswill hold the sliding edges in abutting relation without permitting themto overlap under torsional stress, it is preferred to provide handles 30as shown in FIGS. and 6 for ease of gripping without slipping. Thehandles are of flexible material and are molded to provide checkeredtype gripping surfaces 32 to prevent slippage of the hand both inpulling and twisting. Annular ribs 36 and 38 provided at the ends of thehandles assist in locating and holding the hands in proper position forall muscular exercises indicated and the outer ends 40 of the handlesare closed by an integral end wall to protect both the hands and the barends against injury and damage.

A non-hardening rubber base adhesive 42 is employed to adhere thehandles to the bar ends and the adhesive and resiliency of the handlematerial cooperate with, rather than impede, the sliding action of theside edges 16 at the slit 20.

Moreover, it will be observed that the tubular structure of theinvention cannot be physically bent by the hands during muscularexercise, the radius of gyration being infinitely greater in preventingthis than that which would be present with lesser girth and the samecrosssectional area of the metal present if the metal is present in theform of rod stock having a diameter approximately .300".

While the invention has been described in terms of a preferredembodiment and a modification thereof, its scope is not intended to belimited by the precise embodiment herein shown; and it is understoodthat details of the structures shown may be altered or omitted withoutdeparting from the spirit of the invention as defined by the followingclaims.

4 What is claimed is: 1. An exercise bar for the muscles of the uppereX- tremity comprising a tubular member of rolled metal of optimumlength and resilience and of a girth, capable of being easily grippedmanually at opposite ends,

said member having at least four circumferentially spaced walls borderedby work hardened corners, one wall including opposing edges defining aslit between them extending longitudinally from end to end of said onewall to permit the member to be twisted in either direction equallyabout its longitudinal axis by the application of a manual torsionalforce at the opposite ends of said member with the opposing edgesmovable relative to each other, and

means rigidifying said member against bending and holding said opposingedges in registry with each other comprising said plurality of corners.

2. An exercise bar as defined in claim 1 including hand grips of aresilient material enclosing the ends of said member and provided withan external checkered hand grip portion.

3. An exercise bar as defined in claim 1 wherein the edges defining thelongitudinal slit are opposing each other in a common plane in abuttinglongitudinally sliding relationship to permit such member to be twistedfrom one position of relative rotation to an opposite position ofrelative rotation through a substantial angular deflection 4. Anexercise bar as defined in claim 1 wherein the edges defining thelongitudinal slit abut each other against overlapping under torsionalstress.

5. An exercise bar as defined in claim 1 wherein the metal comprisingthe rolled tubular member is quarterhard cold-rolled steel strip withthe crystal lattice constituting the work hardened corners oriented in adirection transverse to the grain of the strip.

6. An exercise bar as defined in claim 1 wherein the member is comprisedof flat sides bordered by work hardened longitudinal ribs. 40 7. Anexercise bar as defined in claim 1 including hand grips of a resilientmaterial enclosing the end portions of said member, and resilientadhesive means securing said grips to said member for accommodating saidrelative movement of said opposing edges,

8. The exercise bar as defined in claim 1 wherein said opposing edgescomprise the edges of cold-rolled steel strip and said membercross-sectionally defines an essentially octagonal form with four majorwalls and four minor walls in the nature of recessed mitered corners 50which marginally provide work hardened ribs extending longitudinally ofthe member, said slit being in one of said major walls.

ANTON O. OECHSLE, Primary Examiner W. R. BROWNE, Assistant Examiner US.Cl. X.R. 73 379; '272. 79

